Searches for any of these terms today are now blocked, none of them will auto-complete, the results are being censored in the same way as searches for torrents, illegal content, and illicit pornography.

The issue is absolutely not one of search volume.

A search for "Elizabeth Warren na" shows the following results:

Navient is the first auto-completed term, yet it doesn't even register on Google Trends.

"Elizabeth Warren Native American" on the other hand does register and is actually spiking like crazy.

It's also the second recommended auto-complete term on Bing.

Google can pick up spiking terms and auto-complete them within hours, yet here we get nothing.

This evidence is clear: these highly relevant, heavily searched terms are being actively censored as though they're recommendations for illegal content or illicit pornography.